In recent years, attempts to use stem cells for regenerative medicine and drug development have been made. Because the stem cells have both pluripotency and proliferation potency, any cell can be theoretically manufactured in any amount. As an application example of this technology, there is culturing of myocardial cells. Because myocardial cells are terminally differentiated cells, it is difficult to regenerate myocardial cells that are injured due to ischemic heart disease or the like. Thus, a treatment method of differentiating stem cells into myocardial cells and transplanting the obtained myocardial cells into the heart is considered.
However, the number of cells to be differentiated into objective cells is not necessarily large even when differentiation induction is performed on the stem cells. Thus, when wanting to use cells after differentiation, it is necessary to identify and separate differentiated cells and undifferentiated cells. When an actual application is considered, it is preferable to automatically perform a process of selecting the cells in terms of safety assurance and manufacturing efficiency. Also, it is preferable to perform a non-invasive technique so that the differentiated cells are not injured.
There is technology for tracking the motion of an object within an image as one of technologies for analyzing time-series images. Technology for measuring the pulsations of a heart or myocardial cells from an image in which the heart and the myocardial cells are observed in time series by applying the above-described technology is disclosed in Non Patent Document 1 and Non Patent Document 2. Cultured myocardial cells are characterized in that autonomous pulsation is performed. Therefore, it is possible to identify the myocardial cells differentiated from the stem cells automatically and non-invasively by employing the above-described technologies and the characteristic of the cultured myocardial cells.